Impact tools



E. SUSSMAN IMPACT TOOLS May 4, 1965 2 Sheets-Sheet 1 Filed NOV. 13, 1961 w 0 w z a a ,0 6 i w, y; a i a W w a z w a W WI, z 7 W a y Z a w INVENTOR 2 9723? fiws ATTORNEYS E. SUSSMAN IMPACT TOOLS May 4, 1965 2 Sheets-sheaf. 2

Filed NOV. 15, 1961 x XXXXX xx Mvmv mwawm 1 \Irl.

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BY 041;, M, M d J;

ATTORNEYS United States Patent 3,181,626 IMPACT TOOLS Ernst Sussman, Bierys Bridge Road, Bethlehem, Pa. Filed Nov. 13, 1961, Ser. No. 151,970 11 Claims. (Cl. 173-53) This invention relates to impact tools and more particularly to impact tools in which the hammer spring may be cocked prior to application of the tool to a work piece.

Impact tools of various kinds are well-known in the art. These impact tools are all provided with an impact head which forms the working end of the tool. This impact head may be, for example, a conical center punch, an engraving punch, a hollow punch, a nail or staple driver, an electrical pin connector or inserter, or any other type of elementary tool adapted to function under the action of a sharp impact. The known impact tools referred to above generally comprise a movable outer member such as a handle which may be moved with respect to the other portions of the tool to compress a spring bearing against an inner movable hammer retained by appropriate pawls or other types of latching arrangements. When the spring has been compressed to the desired extent, the pawls or latching devices are automatically disengaged and the hammer moves under the influence of the compressed spring to deliver an impact to the head of the tool.

It is a primary object of this invention to provide an impact tool in which the hammer spring is compressed and retained in a cocked position prior to application of the impact tool to the work piece.

It is another object of this invention to provide an impact tool which, in certain applications thereof, may be utilized to test the results of an impacting operation as the tool is being cocked in preparation for a subsequent operation.

It is a further object of this invention to provide an impact tool which will automatically cock the hammer and hammer spring upon the completion of an impact operation.

It is yet an other object of this invention to provide an impact tool having selectively operable means for automatically recocking the hammer and hammer spring if desired.

With these and other objects in view, the present invention contemplates an impact tool comprising a body portion and a handle telescopically disposed thereon. An anvil is slidably mounted within an aperture in the body portion at the end thereof opposite the handle. A hammer is slidably disposed within the body portion and a hammer spring is interposed between the hammer and an abutment formed on the interior of the body portion. Lost motion means are provided for connecting the handle to the hammer member whereby movement of the handle along the body and away from the anvil will compress the hammer spring. A latch is provided for engaging and holding the hammer in a cocked position when the hammer spring has been compressed to the desired extent. A c amming arrangement is provided for releasing the latch upon movement of the handle toward the anvil to enable the hammer to deliver an impact to the anvil. A recock ing spring is interposed between the handle and the body and selectively operable means are provided for compressing this spring, when desired, as the handle is moved toward the anvil to release the latch. When hand pressure is removed from the handle, this recccking spring will move the handle and hence the hammer away from the body and anvil to compress the hammer spring and recock the device. The spring constant of the recocking spring is sufliciently large toenable it to provide sufiicient force to effect the recocking.

3,181,626 Patented May 4, 1965 Other objects, advantages and novel features of the invention will become readily apparent upon consideration of the following detailed description when read in conjunction with the accompanying drawings wherein:

FIGURE 1 is a longitudinal section through a preferred embodiment of the present invention with the hammer and latch in the cocked position and with the recocking spring compressing members in their inoperative positions;

FIGURE 2 is a view similar to FIGURE 1 in which the handle has been moved forward to disengage the hammer latch and the hammer has delivered an impact to the anvil;

FIGURE 3 is a view similar to FIGURE 2 in which the recocking spring compressing members have been moved to their operative position and the recocking spring has been compressed as the result of the movement of the handle to eifect an impacting operation;

FIGURE 4 is a perspective view of several internal parts which comprise the body portion of the tool;

FIGURE 5 is a sectional view taken along the line 5-5 of FIGURE 1 and illustrates the recocking cam with the recocking spring compressing members in their inoperative positions;

FIGURE 6 is a view similar to FIGURE 5 and illustrates the positions of the recocking cam when the recocking spring compressing members are disposed in their operative positions;

FIGURE 7 is a detail of the body portion and illustrates the grooves which accommodate a key carried by the handle;

FIGURE 8 is an elevation view of the impact tool of the present invention provided with a center punch type of impact head; and

FIGURE 9 is a fragmentary view similar to FIGURE 8 and illustrates a typical electrical terminal inserting head which may be used with the impact tool of the present invention.

Attention now is directed to the drawings, wherein like numerals of reference designate like parts through the several views, and more particularly to FIGURES 1 to 3. The impact tool of the present invention comprises a body portion and a handle designated generally by the reference numerals 1t and 11, respectively. The body portion is formed of a guide 12, a cam 14, and a barrel member 15. The guide 12 is threaded into the inner end of the barrel member with the cam 14 disposed between the end of the barrel member 15 and a flange 16 formed on the guide 12. This relationship of these parts is best illustrated in FIGURE 4. The handle 11 comprises a sleeve 18, a bushing 19, and a cap 20. A portion of the sleeve 13 is spun into a groove formed in the bushing 19 as indicated at 21 to connect these two parts together and the cap 21} is threaded into the bushing 19 as shown to provide a smooth exterior for the handle.

An anvil 22 is slidably disposed within the barrel member 15 and is provided with a shank 24 which projects through the free end of the body member. The shank 24 is threaded on the free end thereof (FIGURES 8 and 9) to accommodate various types of impact heads. A spacer sleeve 25 (FIGURES 1-3) is disposed within the barrel member 15 and abuts the inner end of the guide 12. An anvil spring 26 is provided for normally urging the anvil 22. into contact with the spacer sleeve 25. A hammer 28 is slidably disposed within a central aperture 29 formed in the guide 12. A hammer projecting spring 39 is interposed between the inner end of the guide 12 and a head 31 formed on the hammer 28. A latching member 32 is disposed within a slot 33 formed in the interior of the guide 12, and has its forward end pivotally received in the forward end of said slot. The latching member 32 is provided with a projection 34 which engages an annular groove 35 formed in the hammer 28 to normally preclude movement of the hammer under the the hammer spring '30.

A recocking spring retainer 36 is disposed within the influence of a handle 11 and is provided with flanges 38 and 39 at the a;

36 against the bushing 19 as well as urging the handle 11 to its retracted position.

The guide 12 is further provided with threecircumferentially spaced longitudinal slots 42 (FIGURE 4). A recocking spring compressing member 44 (FIGURES 1 to 3) is disposed within each of the slots 42. A garter spring 45 is disposed within an annular groove 46 formed in the guide 12. The groove 46 communicates with the slots 33 and 42 so that the garter spring 45 engages the latching member 32 and each of the spring compressing members 44. The garter spring will normally urge. all of these members to the positions shown in FIGURE 1."

A key 48 is secured to the inner wall of the sleeve 18 l with one side of the slot 50. The exterior of the sleeve 18 and barrel member 15 are provided'with indicia, designated. generally by the reference numeral 52, which serves 7 A portion of the key 48 projects beyond the.

shown in FIGURE 5 with recesses 59 radially opposite end portions 60 of compressing members 44. The garter spring 45 pivots the ends 60. of the members 44 into the recesses 59 This position is best illustrated in FIG- URE 1. I p

The tool is then ready for'an impacting operation and thetapered pin connector 56 is inserted in the recess 55 'as shown in FIGURE 9. The tip of the connector 56 is then positionedin a tapered aperture 61 formed in a mating connector 62. The handle 11 is then gripped by the operator and pushed along the" body portion (to to indicate to the user in which position the key 48 is disposed. a

. Operation In order that a better understanding of the invention might be had, its mode of operation will now be described. Since the impact tool of the present invention may be'cocked and operated in two difier'ent manners, these will be described separately. The first of these is the single-operation in which the tool is recockedfmanually. The body portion 10 and handle'll are first relatively rotated to position the indicia 52 as illustrated in -30 to the cockedposition shown in FIGURE 1.

FIGURE 8 with the arrow pointing to the word Single.

Any-of-various impact heads may then be attached to the tool by threading onto the shank 24. For purposes, of illustration, the Single operation of. the impact tool will be described in connection with a taper pin inserter' a 54 (FIGURE 9) since the manual cocking a'rrangement has particular utility'in connection with the insertion of taper pin connectors. The inserter54 is provided with tion 10 have been pulled to'the positions shownin FIG- URE 1, the garterspring; depresses the latching mern- V a recess '55 which accommodates a taper pin connector the right in FIGURE 1). As thehandle 11 moves to the right, aconical cam surface 64 formed on the bushing 19 engages the latching memberi32 and moves it to the position. shown in FIGURE 2. This movement of the latch! ing member 32 withdraws the projection 34 from the groove 35 and permits the hammer spring 30 to move thehammer 28 to bring the head 31 into contact with the anvil 22. The impact of the head 31 on the anvil 22 is transmitted to the connector 56 by virtue of engagement of shoulders with an annular flange 66 formed on the connector 56; The impact drives the connector 56 into the tapered aperture 61 and into firm frictional engagement therewith. FIGURE 2 illustrates the relationship of the various parts immediately after the head using the inserted connector 56 to restrain one end of the tool during this recocking operation, the connection between the connectors 56 and 62 is tested by the application' of the force necessary to compress the hammer spring The spring constant of hammer spring' 30 is selected so that the recocking force is equal to the desired testforce. If the'co'nnecti on is a faulty one incapable of'withstanding the test force, then theconnectors will separate before the tool can be recocked. If it is not desired to test the connection thus made, or if an impact head other than the taper pin inserterj54 is used, then the tool may be" manually recocked in the manner'previously described.

In many applications ofimpa/ct tools, it is desirable to eliminate the manual recockingoperation. This may be accomplished in the following manner with the impact tool of the present invention. 7 portion 10 are rotated so that the arrow of .the indicia 52 isin the Repeati-position. "The key 48 is then disposed against the opposite side of the slot 50; It. should be noted. that the slot 50is provided with elongated portions '69 which serve to accommodate the key 48 as the handle ll'is moved forward along the body portion 10. Rotation of the handle l l has caused rotation or the cam 14 A retract-' ber 32 to engage the projection 34 in the. annular gro'ove 35 and retain the hammer 28 in the cocked position; When the handle 11 and body portion ltl were rotated to rthe positions shown in FIGURE 8,'the key 48 caused the'cam 14-to' rotate; with the handle 11 while the com-1' pressing members 44 were precluded from-rotating therewith by the sides of the slots 42 which remain fixed in 1' position relative tofthe body portion 10. The cam -14 and compressing members 44 thus'assume the'po sitions V to the position shown in FIGURE 6. Again, the compressing members 44"have been prevented from'rotating with the handle 11 by'the sides ,o'f the slots 42; The

0am surfaces defined by the slots 59 on the cam 14engage the ends '60 of the members and push them to the'bottom of the slots 42 against the urging of the garter spring 45 as the cam '14 is rotatedt-o the position shown in-FIG- URE 6. Themembers 44are then disposed parallel to the longitudinal axis of the .tool and in alignment with the recockingspring 40. 'Ihis position' of the member's as the center punch head sho'wnin FIGURE 8., The

' Qtool may. then be initially cocked manually as previouslyv isbest illustrated in FIGURE 3. The impact tool may then be equipped with'any of various impact heads such described. V v The toolis then-pl aced with the tipfof the center punch touching the =work piece "(not shown) 'as the 'point The handle ll and body where a center punch mark is desired. Again the handle 11 is moved along the body portion to trip the latching member 32 and deliver an impact to the center punch 70. In this instance however the recocking spring 40 is further compressed by this movement of the handle 11 along the body portion 10 since the right-hand end of the spring 40 is engaged by the ends of the compressing members 44 as the handle moves to the right. The retainer 36 is provided with slots 71 which accommodate the ends of the compressing members 44 and thu permit the retainer 36 to move with the handle 11 as the spring 40 is being compressed. It will be noted that the recocking spring 40 was not compressed during the Single operation because the ends of the compressing members 44 were pivoted away from the end of the spring 40 as hown in FIGURE 2. After the impact has been delivered to the center punch 70, the operator releases the pressure exerted on the handle 11. The compressed recocking spring 40, acting on the handle 11 through the flange 38 and on the body portion 10 through the compressing members 44, forces the handle back along the body portion. Again the bushing 19 engages the head 58 to compress the hammer spring 30 and automatically recock the tool. A was previously mentioned, the spring 40 is initially compressed between the flanges 38 and 39. The spring constant of the spring 40 and the initial compression thereof are calculated to exert a sufficient force to overcome the hammer spring 30 and recock the tool. When the tool has been automatically recocked in this manner, the spring 40 is still in engagement with the ends of the compressed members 44 and is just slightly lifted away from the flange 39. This arrangement is necessary in order that the tool may be completely cocked. The compressing members 44 are provided with level surfaces 72 which enable the members 44 to cam the righthand end of the spring 40 slightly away from the flange 39 when the members 44 are initially pivoted to the position shown in FIGURE 3.

It will be obvious from the foregoing description that a new and improved impact tool is provided by the present invention. The tool is susceptible of either manual or automatic recocking dependent upon the operation involved and the desires of the operator. Although the invention has been disclosed in connection with center punch and taper pin inserter impact heads, it will be obvious to those skilled in the art that the tool of the present invention may be used with equal facility with all types of impact heads. Although the single operation has been described in connection with a taper pin inserter and the repeat operation has been described in connection with a center punch, it is obvious that these could be reversed. The tool will function equally well to insert taper pins in the repeat position although the testing by recocking operation cannot be performed and center punching can be accomplished with the tool in the single position although manual recocking will then be necessary. The nature of the operations to be performed will be the deciding factor in determining which position is to be used. The repeat position has particularly utility in operations such as punching and driving variou types of fasteners when used in conjunction with an appropriate magazine feed for the fasteners.

It is to be understood that the above described arrangements are simply illustrative of a preferred embodiment of the invention incorporating the principal features thereof. Numerous other arrangements and embodiments may be readily devised by those skilled in the art to achieve a similar device which still embodies the principles of the present invention and falls within the spirit and scope thereof.

What is claimed is:

1. An impact tool comprising:

(a) a tubular handle (b) a hollow body portion telescopically movable within said handle,

(c) an anvil slidably disposed within said body portion,

6 and carrying a tool head projecting from said body portion, (d) a hammer slidably disposed within said body portion (e) resiliently compressible means interposed between said hammer and an abutment fixed on said body portion so as to normally urge said hammer toward said anvil,

(f) tnactive means connecting said hammer to said handle whereby retractive movement of said handle along said body and away from said anvil will pull said hammer reariwaridly and compress said resilient means between said hammer and said body portion abutment,

(g) latch means for engaging and holding said hammer in a cocked position when said resilient means has been compressed to the desired extent, and

(h) means on said handle for disengaging said latch means when said handle is moved along said body portion toward said anvil whereby said hammer delivers an impact to said anvil under the influence of said resilient means.

2. An impact tool as defined in claim 1 wherein said tractive means comprises a lost motion device including an enlarged head formed on the rearward portion of said hammer and disposed within a counterbored recess in the end of said handle whereby movement of said handle in one direction causes corresponding movement of said hammer while said handle may be moved in the opposite direction independently of said hammer.

3. An impact tool as defined in claim 1 wherein said latch means comprises an elongate member pivoted on said body portion for movement in a radial plane and having a projection thereon adapted to engage an annular groove formed in said hammer.

4. An impact tool as defined in claim 3 wherein said disengaging means comprises a cam carried by said handle and adapted to engage the free end of said elongate member as said handle is moved toward said anvil and pivot said elongate member to move said projection out of said groove whereby said hammer is free to move under the influence of said resilient means.

5. An impact tool comprising:

(a) a tubular handle having an open end and a closed end,

(12) a hollow cylindrical body portion telescopically disposed within the open end of said handle,

(0) an anvil slidably disposed within said body portion having a shank thereof projecting beyond said body portion and away from said handle,

(d) a guide disposed within said handle and secured to the inner end of said body portion,

(e) a hammer slidably disposed Within said guide and having an enlarged head formed thereon and disposed within said body portion,

(f) a helical spring interposed between the enlarged head on said hammer and the inner end of said guidie and normally urging said head toward said anvi (g) an enlarged portion formed on the opposite end of said hammer and disposed within a counterbored recess in the closed end of said handle to provide a lost motion connection between said hammer and said handle whereby movement of said handle away from said anvil causes corresponding movement of said hammer to compress said helical spring while said handle may be moved in the opposite direction independently of said hammer,

(h) an elongated latching member pivoted in a longitudinal slot in said guide for movement in a radial plane and having a projection thereon adapted to engage an annular groove formed in said hammer for holding said hammer in a cocked position when said helical spring has been compressed to the desired extent,

(i) resilient means on said guide normally urging said latching member toward said hammer, and. (j) and. a cam carried by said handle and adapted. to

engage the free end of said latching member as saidhandle is moved toward said anvil and pivot said latching member to move said projection out' of said groove whereby said hammer is free to' deliver.

latch has been tripped the handle is projected rearwardly' away from latch releasing position whereby the latch is again engagedfan'df the hammer cocked,

j 8. The'impact tool as'definedL in claim7'injwhich' there are provided movable. abutment means. carried by one of the recited parts between which the saidsecond spring is disposed, andfmanually operable means for adjusting said' abutment means into and out of positions of operative contact with the adjacent end of said spring. 9. The impact tool as defined in claim 8' in which said adjustable means includes at least one member pivoted on said body portion for movement inia radial plane between first and second positions, said pivoted element" being operative "to engage said strong re-cocking spring ment in radial-planes and normally pivoted toward a the longitudinal axis of said tool by said resilient V means, r

(n) the rear-ward ends of said compressing members being accommodated in. axial slots formed in said spring retainer and being disposed inside the cylindrical plane defined by said recocking spring when in their innermost positions, and

(0) carrrmeans carried by said handle and operable ,upon relative rotation between said handle and said body portion for pivoting said' compressing mem-- bers into the cylindrical plane of saidre'cock ng spring whereby said recocking spring will engage the ends of said compressing members and be fur ther compressed upon movement of said han'dle to-t ward said anvil. a 7. An impact tool comprising: (a) a hollow tubular body portion,

(b) an anvil slidably disposed within said bodyjpor tion and carryinga tool head projecting from said body portion,

(c) a hammer slidably disposed within said body portion, 7 I

(d) a projecting spring within said body portion compressed between saidvbody portion and said hammer for projecting said hammer toward said anvil when releasedfrom compression, 1

. (e) a handle member operatively connected with said hammer to retract it against theur'ging' of said spring, (1'') latch means for engaging and holding said hammer in a cockedposition upon retraction thereof a said spring toa predetermined point,"

(g) trip means also actuated by saidhandlefor ir egainst to effect compression thereof asisaid. handle is' moved toward said anvil only when said'pivotedmember is disposed in said second position, and a cam device operatively' connected with said handle and adjustable upon rotative movement of saidhandle to swing said pivoted member to'and from said first and second positions.

10. The impact tool asfdcfined. in claim 9 in which there is provided a narrowed substantially cylindrical, extension on the rearward end of said body portion along side of which said. ivoted adjustable re-cocking spring engaging member is disposed, said latchcomprising an elongated element'pivoted upon apart of said body portion and alsodisposed alongside of said cylindrical ext'ension; in which the second or engaging position of said adjustable pivotal member' isa radially outward one and the engaging position of said. latch is a radially inward oneaand in which a garter spring surrounds both thegaged position against'the respective actions of the'cam device and thelatch trip means.

11. The impact tool as defined in claim 10 in which the cylindrical extension of the bodyportion is' provided with radial slots; accommodating the movement of said. adjustable pivoted members and said latch element, and a circumferential jgroove intersecting said slots and ac- I commoda'ting said garter spring. v I

References Cited by the Enaminer I V I UNITED STATES PATENTS 1,720,318

SAMU'ELJROTHBERG, Examiner. 

1. AN IMPACT TOOL COMPRISING: (A) A TUBULAR HANDLE (B) A HOLLOW BODY PORTION TELESCOPICALLY MOVABLE WITHIN SAID HANDLE, (C) AN ANVIL SLIDABLY DISPOSED WITHIN SAID BODY PORTION, AND CARRYING A TOOL HEAD PROJECTING FROM SAID BODY PORTION, (D) A HAMMER SLIDABLY DISPOSED WITHIN SAID BODY PORTION (E) RESILIENTLY COMPRESSIBLE MEANS INTERPOSED BETWEEN SAID HAMMER AND AN ABUTMENT FIXED ON SAID BODY PORTION SO AS TO NORMALLY URGE SAID HAMMER TOWARD SAID ANVIL, (F) TRACTIVE MEANS CONNECTING SAID HAMMER TO SAID HANDLE WHEREBY RETRACTIVE MOVEMENT OF SAID HANDLE ALONG SAID BODY AND AWAY FROM SAID ANVIL WILL PULL SAID HAMMER REARWARLY AND COMPRESS SAID RESILIENT MEANS BETWEEN SAID HAMMER AND SAID BODY PORTION ABUTMENT, (G) LATCH MEANS FOR ENGAGING AND HOLDING SAID HAMMER IN A COCKED POSITION WHEN SAID RESILIENT MEANS HAS BEEN COMPRESSED TO THE DESIRED EXTENT, AND (H) MEANS ON SAID HANDLE FOR DISENGAGING SAID LATCH MEANS WHEN SAID HANDLE IS MOVED ALONG SAID BODY PORTION TOWARD SAID ANVIL WHEREBY SAID HAMMBER DELIVERS AN IMPACT TO SAID ANVIL UNDER THE INFLUENCE OF SAID RESILIENT MEANS. 